Fair Value Measurements - Summary of Fair Value Measurements for Items (Details) - USD ($)
$ in Thousands
Mar. 31, 2021
Dec. 31, 2020
Dec. 31, 2019
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]      
Total assets at fair value $ 35,799 $ 53,963 $ 56,428
Total liabilities at fair value 62,039 142,592 156,233
Public Warrants [Member]      
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]      
Total liabilities at fair value 44,436    
Private Placement Warrants [Member]      
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]      
Total liabilities at fair value 17,603    
Derivative Liabilities [Member]      
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]      
Total liabilities at fair value   44,810 138,561
Warrants Payable [Member]      
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]      
Total liabilities at fair value   97,782 17,672
U.S. Government and Government Agencies [Member]      
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]      
Total assets at fair value 35,799 53,963 56,428
Level 1 [Member]      
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]      
Total assets at fair value 0 0  
Total liabilities at fair value 44,436 0  
Level 1 [Member] | Public Warrants [Member]      
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]      
Total liabilities at fair value 44,436    
Level 1 [Member] | Private Placement Warrants [Member]      
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]      
Total liabilities at fair value 0    
Level 1 [Member] | Derivative Liabilities [Member]      
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]      
Total liabilities at fair value   0  
Level 1 [Member] | Warrants Payable [Member]      
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]      
Total liabilities at fair value   0  
Level 1 [Member] | U.S. Government and Government Agencies [Member]      
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]      
Total assets at fair value 0 0  
Level 2 [Member]      
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]      
Total assets at fair value 35,799 53,963 56,428
Total liabilities at fair value 17,603 0  
Level 2 [Member] | Public Warrants [Member]      
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]      
Total liabilities at fair value 0    
Level 2 [Member] | Private Placement Warrants [Member]      
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]      
Total liabilities at fair value 17,603    
Level 2 [Member] | Derivative Liabilities [Member]      
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]      
Total liabilities at fair value   0  
Level 2 [Member] | Warrants Payable [Member]      
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]      
Total liabilities at fair value   0  
Level 2 [Member] | U.S. Government and Government Agencies [Member]      
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]      
Total assets at fair value 35,799 53,963 56,428
Level 3 [Member]      
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]      
Total assets at fair value 0 0  
Total liabilities at fair value 0 142,592 156,233
Level 3 [Member] | Public Warrants [Member]      
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]      
Total liabilities at fair value 0    
Level 3 [Member] | Private Placement Warrants [Member]      
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]      
Total liabilities at fair value 0    
Level 3 [Member] | Derivative Liabilities [Member]      
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]      
Total liabilities at fair value   44,810 138,561
Level 3 [Member] | Warrants Payable [Member]      
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]      
Total liabilities at fair value   97,782 $ 17,672
Level 3 [Member] | U.S. Government and Government Agencies [Member]      
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]      
Total assets at fair value $ 0 $ 0